Experiments
by SuperWhoCaskettLock
Summary: When Alexis is attacked and her friend is murdered, Detective Beckett and her partner dive into the murder case, desperate for answers. However, they have no idea that the reason behind this particular murder is both supernatural and very human.
1. Run For Cover

**A/N: I do not own any of the characters or the show. If I did, the hiatus would be much shorter.**

Alexis grinned at her friend, raising one eyebrow teasingly as she caught her staring friend's eye. The girl opposite Alexis blushed furiously, her head dipping to stare at her food as she tucked her lips in to attempt to hide her smile.

"Who're you looking at?" Alexis asked teasingly, not bothering to keep her voice hush. The blush worsened on the other girl and she glared at Alexis before nodding her head lightly towards a man sitting alone at the table next to them. He had dark brown hair and a perfectly aligned face, and a fierce jaw line that, at first glance, Alexis felt the need to run her fingers across. His light blue eyes met the girl's stares, and a small smile crossed his beautiful face. Alexis dropped her view, looking back at her friend, who was now looking at her.

"He's hot," she said in reply to her friend's unanswered question. Her friend grinned and nodded her head lightly before turning her attention back to her food, or what was left of it. "You should go talk to him."

Her friend's eyes widened at the suggestion and she shook her head. "No way," she said quietly with a small, shy smile. That was the thing about Amber, her smiles were always small and she hardly spoke. Alexis didn't mind, though, Amber and she had grown close in these past few months despite her quiet nature.

"Oh come on," Alexis teased with a light hit to her friend's arm.

"Fine," her friend said, looking back at the man and they met eyes once again. But this time there was a change, in both Amber's face and the man's eyes. Amber clamped her mouth shut, regretting saying a word and opening her mouth in the presence of a strange man. Her face fell and her eyes screamed terror as the man's eyes screamed hunger.

"I'll pay," Amber said quickly, ignoring Alexis's confused look as she tucked the money under a napkin and grabbed Alexis by the arm, dragging her out of the restaurant and out onto the dark, unlit street. Amber let out a breath as they reached the sidewalk, beginning their walk down the street.

"What was that all about?" Alexis asked her friend, aware of the grip her friend still had on her arm. Amber simply shook her head in reply and looked back, her heart shot with terror as she saw the man had followed them outside.

Amber swore and gripped Alexis tighter, desperate for her friend's comfort as her heart filled with fear and anxiety as their walk sped up. Before Alexis could protest, they were running, the man not far behind. Alexis snuck a glance backwards and saw the man following. It was only then that she noticed that another person was also following them, a girl about their age.

Her eyes widened and she picked up speed, knowing that both she and her friend were in danger, and that they needed to get somewhere safe as soon as possible. She dragged her friend into an alley to their left, not bothering to check if it was a dead end or not. When they nearly slammed into the wall at the end, Amber's breath stopped in fear as she clutched Alexis's arm tighter. Alexis, keeping as calm as possible, whipped out her cell phone and quickly dialed a number.

The young girl nearly threw up her dinner as her phone warned her that she had no service and the man stopped right in front of the alley entrance, spotting the two girls and grinning wickedly. Amber was shaking as she leaned against Alexis, who had pushed her friend back in front of her in a desperate attempt to protect her.

"Leave us alone!" Alexis said loudly, cursing herself when her voice shook slightly. The man said nothing but grabbed Alexis by the neck, throwing the girl into the right wall before anyone could protest. As Alexis attempted to breathe, the man was already on Amber, knife nearing the young girl's neck. She screamed, desperately calling for Alexis, who was struggling to stand, something that she had seemed to forgotten how to do.

With a final scream Amber dropped to the ground, clutching at her throat as though she could stop the flow of blood that leaked out. The man turned to Alexis, who was on the ground, frozen with terror and pleading up at the murderer in front of her. The man had changed from when she saw him in the restaurant only minutes ago, he was now wearing black gloves and a toque, as though scared some of his hair would fall onto his victims.

Alexis sobbed and braced herself for the impact of the knife against her throat. A thousand questions ran through her mind, but only two faces; her father and her grandmother's. If only she could see them one last time, truly tell them how much she loved them and was grateful for them. She knew how hard it was going to be for her father to see a scene like this happen to his own daughter, she only hoped that Beckett would be there to catch her father when he fell; arms wide open to give him comfort.

God, she wished it didn't have to end this way.

The knife finally slashed, but just as it flew across where Alexis's neck should have been, a firm arm pulled her away so quickly that her breath caught in her throat and her ankle twisted painfully. She was thrown onto the ground as someone leaped up and assaulted the man, turning his weapon against him. Yelping in pain at the knife in his shoulder and cursing the attacker, he decided Alexis wasn't important enough for him to risk his life on and he ran out of the alley before any of his blood could hit the ground.

Panting furiously, the attacker crouched down in front of Amber's limp body. She was careful not to touch it, not wanting to be a suspect in the murder case that was sure to follow. Thankfully, all she needed was one look to ensure that this was the same girl she'd had her eye on for the past few weeks. She let out a sigh of regret and stood again, turning back to look at Alexis; who was now on the ground after being thrown into two trash cans. Alexis was surprised to see that her hero was a girl about her age, who was now looking at her. "You alright?" She asked, her voice unnaturally calm and smooth for just attacking someone with a knife. Alexis nodded but let out a squeak of pain as her ankle seemed to twist on her again. The girl crouched down in front of her, lightly wiping the hair away from Alexis's eyes and removing something from her coat pocket. Her touch was surprisingly gentle, but once she reached into her pocket Alexis's heart stopped in fear for a moment.

The girl pulled out a phone, quickly dialing the NYPD, a number she knew off by heart. "Hi, I'm calling to report a murder." As the girl gave their location, Alexis focused on the features of her hero the best she could in the limited light of the dark alley. She had dark brown hair, and piercing brown eyes that resembled a bird. Once she hung up the phone, she pocketed it, praying that they didn't come after her.

"Stay golden," she told to Alexis with a large smile as she turned and ran off towards the dead end, disappearing as though she was a ghost.

* * *

"Oh, Richard, dear, put some pants on!"

Richard Castle awkwardly stood in the doorway of his study, stopping mid-chew as the words left his mother's mouth. He was wearing his favorite robe, leaving it untied to reveal that he was wearing nothing but boxers underneath.

"Mother!" He yelped with a mouthful of food, quickly tying up his robe, ignoring the crumbs that spread all over the ground. "What are you doing here?"

"I live here, Richard!" Martha said with a face and a grin as she made her way into the kitchen, clutching a script that Rick knew better than to question. He finished what remained of his muffin and followed her into the kitchen, awkwardly not making eye contact.

"Morning," a familiar voice said from the top of the stairs.

"I hope you're wearing clothes!" Martha said simply, waving as she kept her eyes on the script that now sat on the table.

"Morning," Rick said with a smile, ignoring his mother's comments as he approached Kate, who was at the bottom of the stairs now, giving them both a questioning look. She had hardly a second to absorb what was going on before Rick's lips crashed into hers, and they embraced into a loving kiss for a moment before she pulled apart with a smile. "Sleep well?"

"Actually, not really," Rick said with a shrug, heading back towards the kitchen to make some coffee for his girlfriend. "I passed out at the computer."

Kate rolled her eyes. Instead of filling the night with their usual _activities_, Rick had been on a roll last evening, typing away at his computer for hours. Too exhausted to stay up, Kate had kissed him goodnight and headed up to bed. Hours into the morning, Rick had passed out with his head on the laptop, not to anyone's surprise. Martha had arrived from the Hamptons last night when he was writing and had hardly said a word as she headed to bed, therefore causing Rick to completely forget her arrival.

Kate's phone rang as Martha began reciting her script out loud, dramatic flair and all. Rick chuckled and muttered a "thank god", causing Kate to roll her eyes but smile.

"Beckett," she answered.

"Kate," replied the man on the other line. It was detective Kevin Ryan. "There's been a body."

"Where?" Beckett asked, cop mode activated. His tone of voice put her on high alert and made her stomach do a turn.

Ryan gave Beckett the address, but before she could do so much as move or tell Rick, Ryan interjected. "Get over here as soon as possible. And bring Castle, and his mother, if they're home."

"Why?" Kate asked cautiously Rick's head rose, concern written all over his face.

"It's Alexis," Ryan said.

"A-Alexis?" Kate managed to spit out, panic in her voice. Rick's elbow almost slipped off the counter and he instantly paled, and Martha grew silent.

"She's alright, but get down here right now." With that, Kevin Ryan hung up and Kate grabbed Rick by the arm, nodding for Martha to follow them. No one spoke as they got into the car and drove towards the scene. Despite Ryan reassuring Kate that Alexis was alright, she couldn't help but worry immensely. And by the looks on the faces of her companions, they were feeling the same way.

**A/N: Thank you for reading and please take the time to leave a review! :)**


	2. Brave Face

**A/N: Thanks for the reviews guys! **

**And about that one review: Beckett wasn't coming from his bedroom that morning. She was coming from upstairs, she'd left his bedroom earlier while he was still passed out at his computer. I honestly don't know where specifically she was coming from, I just know it was upstairs. **

Detective Ryan held the young girl's hand as her lip quivered, every word she spoke fading as she attempted to recall the horrifying experience she'd just had to live through. The cops had arrived only minutes after the girl had left, and they immediately rushed to the body, not noticing Alexis for a few moments. In pain and in shock, the girl had kept silent until someone noticed her and called the paramedics over. Now, she was sitting on the back of an ambulance, feet on the asphalt as she waited for her father to come. She'd overheard the conversation, and immediately after detective Ryan had hung up, he'd turned back to her to continue the questioning. The most Alexis could give him was a description of the man and her friend's reaction when they met eyes, but once she got to the actual murder her throat closed up and she refused to go on further. Understanding her need for space and time to get over her shock, Ryan had stopped with the questions and sat next to her, allowing Alexis to take his hand. He hadn't noticed how much she was shaking until he had to grip her hand to steady her, she looked like she was about to be sick.

Minutes later, a familiar car pulled up, and before it was even at a full stop, Richard Castle hopped out of the passenger seat and ran towards the scene. Martha followed closely behind, followed by Beckett, whose panicked looked faded once she spotted Ryan and Alexis.

"Dad," Alexis said at the sight of her father, her words failing her as she felt his arms wrap around her. She hugged him back the best she could, she had a nasty bruise on her side that made it hard for her to properly hug him back. When he finally pulled apart, she was wrapped into another hug by Martha, and she attempted to hug her back as well. Finally, Kate stepped forward to hug her as well, but she was much gentler and Alexis was more than grateful.

"What happened?" Castle asked, shooting a look at Ryan. His voice was calmer now, and he was no longer in a panic, but he was still incredibly worried.

As Ryan began to recite the story to Castle and Martha, Beckett gave Castle a light touch on his arm as she pulled away from the scene, walking into the alley to the crime scene. She had a job to do, and besides, they needed their family time after a scare like that.

"What do we have?" Kate asked as she slipped on some gloves and crouched down near the body, opposite of Lanie.

"Hey girl," Lanie greeted with a grin. Kate smiled back despite herself. "Amber Middleton, 19. Couple of blunt hits on her head and her neck but final cause of death was her slit throat."

As though on cue, Esposito jogged his way into the alley, a smile plastered on his face at the sight of Kate and Lanie. "Have CSU sweep the area," Kate told him, and he nodded and turned away, but not before sneaking a lustful glance towards Lanie.

Kate held back a smile as she looked at Lanie with a raised eyebrow. "I thought you two were over?"

"You don't get it, you haven't slept with him," Lanie muttered as she wrote something down on her board, avoiding eye contact. Kate chuckled and her head rose at the sound of someone else entering the alley.

"There was someone else here," Rick said, looking at Kate. "Someone who interjected in the double murder and stopped the killer from getting Alexis."

Kate blinked in surprise. "Well their presence at the exact time the killer attacked can't be a coincidence. Maybe we'll get a second set of prints once they sweep the area. Thanks, Castle."

Rick nodded, his eyes lingering on Kate for a moment before he turned away and walked out of the alley, heading back towards Alexis and Martha. Kate let out a breath despite herself, she'd been so worried about how Rick would take this but he seemed to be doing quite well. Now they only had to worry about Alexis.

When she looked back to the body, she was surprised to see Lanie staring at her with a smile on her face.

"What?" Kate asked.

"Nothing," Lanie replied, holding back from grinning as she dropped her gaze again. It was somewhat obvious that Lanie knew, but then again it wasn't really a battle to keep it from her. Lanie seemed to know about their relationship status all the time no matter what. Even though she and Rick have been trying to keep it a secret, it was nearly impossible to hide it from Lanie.

Kate rolled her eyes and rose, giving Lanie an annoyed look before walking away from the scene. She approached the Castle family, who were waiting for her. Alexis smiled shakily at Kate, who responded with a small smile back. She then turned to Rick.

"Castle, take Alexis and Martha home. I'll fill you in tomorrow."

Castle looked like he wanted to protest, but he finally shut up and nodded, giving her a loving look before taking Alexis's hand and leading her and Martha away from the crime scene.

* * *

"Good morning," a familiar voice greeted from Kate's left. She turned her head as her partner strolled in, holding out a coffee for her. She smiled and took it, taking a generous sip as she looked over the murder board. It was the next morning, and she almost thought he wouldn't come. They'd last talked last night, Kate had gone back to her place, and when he called he'd asked why. She'd replied with the answer that he needed some family time. His reply threw her off; he'd said and she was family now. She'd been too speechless to reply properly, and even now, the following morning, she had to bite her lip back to keep from grinning at the sight of him. He leaned against the desk next to her, looking over the board for the first time.

In the middle of the board, the face of the young Amber Middleton smiled shyly at them. A description of her murder was underneath it, and on either side of her were the rough sketches of two faces: a brown-haired handsome man who was labeled as their killer and a long-haired young girl who was labeled as the second witness. There was nary a detail on their faces, Alexis hadn't given a proper explanation.

"Castle," greeted Esposito, who had just approached the couple. "I know it's early notice, but we need to get Alexis in here for questioning."

Kate held up a hand to stop Rick from saying something he might regret. "What do you mean by questioning?"

"She's our only available witness and the only person who got a clear look of the killer's face. Plus, she was right in the middle of it."

Kate let out a sigh and turned her head to face Rick. After a moment of inner conflict, he nodded and walked towards the elevator, going home to get Alexis. Once he was gone, Kate turned back to Esposito, missing her boyfriend already. Every time he left he took a part of her with him, even if it was only for a short time. She smiled, however, and asked Esposito if he'd checked into Amber's background yet.

"I have, and get this, Amber Middleton doesn't exist."

Kate blinked in surprise. "What do you mean?"

"She's in no records anywhere. As far as we know, she doesn't even have a family. We've sent her face everywhere in the city but there are no records of her existing anywhere."

"So it's a dead end." Kate let out a sigh and shook her head. She hated dead ends.

A few minutes later, the elevator doors opened and Rick and his daughter stepped out. Rick's arm was around her shoulders, but she was putting on a brave face despite the obvious trauma she was likely still experiencing. Esposito took her without another word and led her to their sketch artist. Within minutes they had to accurate sketches of their second witness and their killer. Kate took the photo of their killer in her hands, noting how he was obviously handsome.

"Okay, you guys go back to the restaurant and see if anyone recognizes this man," she said, handing Esposito and Ryan the sketch.

Once they were gone, Kate walked off towards the interrogation room where Alexis was sitting, waiting for them. She signaled for him to watch this time and entered the room alone.

"Hey Alexis," Kate said, throwing down her notes and pulling up a seat across from her. She believed everything Alexis had told them, but she needed to know the whole story. "Why don't you start at the beginning."

Alexis let out a sigh, grateful that it was Beckett that was questioning her. "Me and Amber were just going out for dinner. Just two friends, planning on having a good time."

"How was she acting before the man?" Kate asked.

"Normal. She was a quiet person, she hardly spoke or smiled widely but she was a sweetheart and that's why I loved her. When we saw the man, at first we were both attracted. I started... teasing her about him." A sad smile crossed Alexis's face. "When they met eyes, that's when I saw the change."

"Change?"

"She... suddenly looked terrified. And the man had a look on his face that just screamed hunger. Like… he'd been hunting her and he finally found her." She let out a shaky breath and paused for a moment. "And we left. She dragged me out."

Kate raised an eyebrow at her statement and leaned forward, urging her to go on.

"He started following us. When we started running… someone else started following us, too. A girl, about our age. I panicked and… pulled us into an alley. It was a dead end." She shook her head and let out an exasperated laugh. "My phone didn't have service. I pushed Amber behind me, to try to protect her. But he came after me first." She raised her head and pointed towards the large bruise on the side of her neck. "He gripped me by the neck and threw me aside."

From behind the wall, Richard Castle let out a small whimper. It was killing him seeing his little girl all banged up about this, knowing that she was probably traumatized after witnessing a murder, but he couldn't help but feel a little proud at how she was carrying herself. She was strong, and she insisted on telling the full story even though every word hurt her. He made a mental note to get her ice cream later.

Back in the room, Alexis's gaze broke from Kate's and she stared at the table. "And then he killed her. I was up against the wall, I was defenseless. He had the knife… he slashed. That's when she came."

"Did you get a clear look at her?"

Alexis shook her head. "It was too dark. I just remember being thrown backwards into garbage cans as she stabbed him and fought him off. Once he was gone, she looked over the body and then asked me if I was alright. She called the cops and then she was off."

Kate let out a sigh and nodded her head. "Alright Alexis, that's –" Her phone rang through the room loudly, stopping her parting speech. "Excuse me," she said as she stepped outside. "Beckett."

"Girl, you'd better get down here," Lanie said into the phone. "And bring Castle, he'll like this."

Kate raised an eyebrow but said nothing further. "Castle," she called. Rick was by her side in seconds, looking at her questioningly then back at Alexis, who was still in the room. Kate opened the door. "Alexis, you're free to go," she said.

"I want to stay. I want to find the girl who saved me," Alexis said firmly, and Kate could tell there would be no stopping her. Kate sighed and nodded, grabbing Castle's arm and leading him away from Alexis, who was now heading towards the break room to sit down while she waited.

Kate dragged Castle into the morgue, and once she let go he didn't run off to go see his daughter like she expected him to. Instead he looked at Lanie with curiosity. Lanie smiled at him as he threw back the sheet on the victim's face.

Amber looked so at peace, other than the large slit on her throat.

"Castle, you'll wanna see this," Lanie said as she pulled back Amber's lips and revealed two large fangs.

"Now we know why she never opened her mouth," Rick said, his eyes widening and his eyes twinkling with that little-kid-in-a-candy-shop look.

"Another vampire?" Kate said sarcastically, rolling her eyes.

"Not exactly," Lanie said. "But they're real."

**A/N: Reviews are very much appreciated ;)**


	3. Second Witness

**A/N: This is NOT a crossover fiction. If it was, I would have obviously labeled it as so. But thanks for that **_**charming**_** review, anyways.**

Kate's jaw dropped and she couldn't get a word out. Rick, however, covered his mouth in shock and almost squealed.

"A real vampire?!" Rick asked, sounding like he'd just won the lottery. Kate rolled her eyes in annoyance, but she felt almost skeptical now.

"Not exactly. Genetic experiment, I'm guessing."

"That would explain why there's no record of her," Kate said finally, glad for a slightly more logical explanation. "She wasn't human, she was a genetic experiment."

Lanie nodded, dropping the girl's lip to cover the fangs again. Rick's face fell a bit, but the excitement didn't disappear. This was the coolest case ever.

"So she was an escaped experiment?" Kate asked. Lanie nodded again.

"Maybe someone killed her because they found out and didn't want... whatevers roaming the city," Rick said. Kate almost questioned his rational response but thought better of it, instead nodding.

"That's possible. Thanks, Lanie," she said as she turned and headed out the door. Rick shot Lanie an "oh my god!" look before following Kate out.

Lanie looked at them leave and shook her head once they were gone. "I swear, if they didn't drive each other crazy, they'd drive each other crazy," she noted as she covered Amber's head again.

* * *

"We're got nothing," Esposito said with a sigh as he and Ryan approached Beckett and Castle, who were staring at the murder board again. "No one's seen him before tonight. Guy's like a ghost. No one has an idea who he is."

"What about Amber, have any of them seen Amber before tonight?"

He shook his head. "Nada."

Kate turned to look at Rick. "Whoever was hunting her down knew what she was. They probably hunted her down because of that."

"Or maybe it's just a coincidence," Rick added. Kate shook her head.

"Can't be. Someone gets hunted down and murdered and they turn out to be a genetic experiment?" Kate shook her head, knowing that the killer knew and that was the reason she was killed. But who was the killer?

"Alexis, do you know if anyone wanted her? Mysterious phone calls, stalkers, people following her when you two were out, anything like that?"

Alexis, who was sitting on Kate's chair behind them, shook her head for a moment before nodding a bit. "Actually, yeah. She kept getting these mysterious phone calls. And she'd always look pale after them."

"When was the last time she got a call like that?" Rick asked his daughter.

"Two hours before we went out. She almost cancelled, but I convinced her otherwise…" her voice fell and she bit her lip back, turning her attention back to the floor.

Kate turned back to Ryan and Esposito. "Run her phone records. Find out what phone the calls came from, and who owns the phone. Maybe we can find the killer."

The boys nodded and turned away. Kate turned back to the murder board, letting out a sigh. It was getting late; she and Rick had spent all day coming up with new theories, none of which helped even in the slightest.

"I think it's about time we called it a night," Rick said, meeting her eyes, clearly pleading her to come home with him. She held back the urge to roll her eyes and nodded, hopping off the desk and grabbing her coat. "Goodnight guys," she called to the boys behind her as she left with Rick and Alexis.

Once they got home, Alexis headed for bed right away, leaving Rick and Kate alone. Kate threw her coat down and turned to Rick.

"So do you believe now?" He asked her, clearly talking about the case. She couldn't stop herself from rolling her eyes, but she smiled despite herself.

"There's a logical explanation, Castle. There's nothing supernatural about this," she said matter-of-factly as she made her way more into the house, Rick following close behind.

"But it's close enough. And who knows, maybe they are real vampires and monsters out there," he insisted.

"Or maybe not," she laughed, turning towards him and tugging him close. Before he could speak back, she kissed him, silencing him as his attention turned from the case to the kiss. He was still adjusting to the fact that they were actually together now, that he could do this whenever he wanted. Obviously, not at work, for they were trying to keep it a secret. It was hard to keep from taking her hand or giving her a quick kiss at work, but that's why they always came home together. So they could do this in complete freedom.

It was hard to believe that Kate was actually his, after being in love with her for so long he was almost sure she didn't feel the same way. But that night she'd shown up on his doorstep, announcing that she wanted him, was a night that changed everything; and probably for the better.

They finally broke the kiss, smiling at each other for a moment as their hands wrapped together at their sides. Rick felt the familiar feeling of butterflies as he looked into her eyes, and she tugged at his hand as she led him towards the bedroom.

* * *

"You seem to be in a good mood this morning."

Kate Beckett blinked, looking up for the source of the voice. She'd been zoned out with a stupid grin on her face, lost in the thoughts of last night. They hadn't done anything like that since the murder, and it was blissful as always. She cleared her throat, pulling herself back to reality. Esposito was smirking; he'd seen the same look on Rick Castle's face as he loaded the coffee machine only a few minutes ago. He knew what had happened, but he kept it quiet, enjoying her embarrassed face a little bit too much.

"Did you get a hit on the call?" Kate asked in her best cop voice, attempting to wipe all the embarrassment off her face.

"Actually, yes. It belongs to a miss Bethany Hillbaker."

Beckett raised her eyebrows. "They must be connected in some way."

"I have good news, though. We have a match on the cell phone." Esposito handed her a sheet of paper with a photo of a bright blue phone. Kate looked in confusion for a moment before it dawned on her.

"This is the same phone they found smashed at the end of the alley," she said in shock. Esposito nodded.

"But the killer was a man," Kate said in confusion.

"What are you guys talking about?" Castle asked as he entered the room and set down a coffee for Kate. She didn't meet his eyes as she felt the blush returning, and Esposito's smirk grew.

"Ooh, I like that phone," Rick said as he took the sheet from Kate's hands, ignoring her annoyed look at him. "Bethany has this."

Kate's head snapped up. "You know her?!"

"Yeah," Rick said. "She was at one of my book signings. It was weird, she asked a lot of questions about Alexis and her friends."

"When was this?" Esposito asked.

"A few months ago, why?"

"Because Bethany is our second witness," Kate said, removing the sketch from the board and handing it to Castle. "Is that her?"

"No, she looked different. Her hair was ginger and she had a different-looking face…"

"She must have changed it," Kate said, putting the photo back. "So this Bethany girl is our second witness. Get uniforms to bring her in," Kate told Esposito, grateful for this break.

"One problem," Esposito began with a regretful expression. "She doesn't exist, either."

**A/N: Leave reviews! Thanks for reading.**


	4. Have You Seen This Girl?

**A/N: Well I assumed it was implied that it was night. I did state that they entered onto a dark and unlit street. Besides, does it really matter? **

**And as for the rest, you'll find out eventually**

"These dead ends are really pissing me off."

"You're not the only one."

"Same here."

"Is that a new lamp?"

Kate raised her eyebrows at Castle, who was staring intently at the lamp on her desk. She bit her lip to keep from smiling. _I'm in love with a child_, she thought to herself as she turned back to the murder board. Castle looked up when he noticed everyone was staring at him.

"I just… it's nice." He shut his mouth, ignoring the look Esposito was giving him and Kate's small eyebrow raise.

"What we need is to find the second witness," Kate started, ignoring Rick and looking back at the murder board. She stepped forwards and gave the sketch of the girl a light tap. "She's the key. She was following the two girls; she probably knows why the man was hunting Amber."

"What if she was just a bystander?" Esposito suggested. Kate shook her head.

"It's not just a coincidence. Those phone calls tell us that much. She was probably warning Amber to be careful and followed her to make sure."

"Unless she was the guy's partner and she was going behind his back to help Amber but she was just too late," Castle threw in.

Kate nodded. "That'd be even better. We need to find her."

"But we have no idea who she is," Ryan said with a frown. "She's a ghost, just like him. She could be in another state by now for all we know."

Kate sighed and pulled herself back up on the desk, furring her eyebrows in thought. She had to have some sort of connection to Amber.

"Maybe they have a past together," Castle said, as though he was reading Kate's thoughts.

"But there's no way of finding out," said Esposito. The four were fresh out of ideas; they'd tried everything and just ran into a dead end every time.

"Esposito, Ryan, take the sketch and ask around the school Amber attended. Maybe the second witness'd been hanging around the school to keep an eye on Amber."

Grateful for something to do, the boys nodded and walked off. With the boys gone, Castle moved next to Kate, feeling her take his hand as they looked back over the murder board. Something fishy was going on, Castle could almost sense it.

* * *

"Excuse me, have you ever seen this girl?" Esposito asked, holding the sketch out to a girl on campus. She scoffed and walked away.

"I think she liked you," Ryan teased. Esposito rolled his eyes.

"We've been here for an hour and we've got nothing," Javier said. "No one has an idea who she is. She's a ghost."

"Excuse me, have you seen this girl?" He tried again. This time, the young blonde froze.

"Yeah. Yeah, I have."

Esposito stopped in his tracks, turning to the girl. Ryan stopped alongside him, pulling out a pad and pen to write down the information he was about to get. "You have?" Esposito responded.

"Yeah. She's homeless. I've seen her a few times outside my mom's store. I think she was the one who broke in a few times."

Ryan scribbled that down while Esposito lowered his hand. "What do you know about her?"

"I know she used to live not far from here. I've heard her on the phone once. Somehow she managed to afford a cell phone, I guess. Unless she stole it." The girl tucked her hair behind her hair and crossed her arms around her chest, obviously a little uncomfortable talking about someone else to the cops. But she pressed on, knowing by Esposito and Ryan's expressions that it was important that she told them everything. "She talked about some building that she once lived in a couple hours from the city."

"Can you tell me where this building is, exactly?"

* * *

Grinning, Esposito nearly ran into the 12th Prescient, Ryan following closely behind. "Yo, Beckett!" He called, jogging towards the partners, who immediately removed their hands from each other's.

"We got a hit on the second victim's previous home. We're guessing she had family there or neighbors or something," he said with a successful nod.

"Awesome," Beckett said, grabbing the paper and standing up. "We'll go see if we can get anything. You guys try and figure out if there's anything we missed."

Excited that they had a new lead, Castle followed happily.

**A/N: Slightly short… I apologize. And I'm sorry that I keep updating every hour on the hour… I understand it must be annoying if you have this story on alerts. I'm just on a bit of a roll right now.**


	5. Blackout

"Are we there yet?"

Kate narrowed her eyes as she watched the road ahead, resisting the urge to hit the man next to her. He'd been asking that same question every ten minutes and it was getting incredibly annoying.

"If you don't stop asking me that my name won't be the only thing you scream tonight," she said, looking over a bit to see his response. He was speechless, and his mouth was open a little bit as his mind probably filled with mental pictures. She smirked, glad to have shut him up and teased him a bit, and continued to drive.

They were on the road to the address listed on the piece of paper Ryan gave them on their way out. It was way out of town, and quite a far drive. They'd been driving for a few hours and weren't even close yet. It was driving Kate crazy to have to drive this far with Castle as her passenger, but she remembered how important of a lead this was and how much they needed it.

"I say the butler did it," Castle said from the seat next to her. He was staring out the window and seemed to be deep in thought, but clearly about nothing useful.

"There's no butler," Kate said obviously.

"A place this far out and into the countryside? There's gonna be a big house, therefore a butler. So there."

"And why would the butler want Amber dead?"

"I dunno," Castle muttered, defeated. Kate shook her head and didn't bother to reply to her crazy theory that no doubt sprung from his obsession with butlers. He was probably rambling about butlers just to annoy her, so she wouldn't give him the satisfaction. He liked to drive her crazy, but she loved him anyways. The car filled with silence and Castle kept his eyes out the side window.

"What would you say about moving in with me?" Castle said suddenly, still looking out the window. Kate nearly slammed on the brakes in surprise, which wouldn't have ended well for anyone.

"Moving in?" She squeaked, letting the idea absorb into her mind. That was a huge step.

"Yeah, I mean, you're always over anyways…" Rick elaborated sheepishly, his voice low as he didn't make eye contact with her. Kate let out a small sigh. She wanted to say yes more than anything, but something in her mind told her it wasn't time yet.

"I'll think about it," she answered quietly, her tone telling him that the conversation was over, for now. Regretting bringing it up, Rick looked out the window again and fell silent, which was unusual.

"What if they genetically experimented on monkeys and made like monkey/tiger hybrids? Wouldn't that be so cool?"

Kate rolled her eyes at his outburst, happy he wasn't too hurt by her decision and that he was back to his old self in a matter of minutes. "Wouldn't that be something," she said flatly, trying not to smile.

"I'd buy one," he added.

They pulled into a long dirt road, one that they couldn't see the end of. Rick's phone rang, and he picked up with an excited greeting of "Castle!"

"Yo, Castle. Are you guys there yet?"

"That's what I keep asking her!" Rick said with a look towards Beckett. She pursed her lips and kept focusing on driving, not giving him the satisfaction.

"Lemme know when you guys get there," Esposito replied, taking the hint.

"Why?" Rick asked, unwrapping a sandwich they'd bought just a bit earlier and finally taking a bite. "Wanna know if we got there safely?"

"I thought something happened, you've been gone for hours."

"That's because Beckett sucks at driving," Rick said in between bites. "Ow!" He yelped as Beckett hit him, but he couldn't help but smirk at her annoyed expression. "And the place is farther than we thought."

"Alright. Good luck."

Castle hung up the phone and slipped it into his jacket pocket, taking another bite of his sandwich just as they pulled up into a graveled road. They snuck a glance at each other as a man on the side of the road waved them to a stop.

Just a short walk away, a large building stood. It looked like a house, a beautifully modern house with a few floors and some lights coming from a couple of windows. Kate drove the car up towards the man, stopping and rolling down her window.

"Do you live here?" She asked. The man leaned down so that he was at eye level with her.

"May I ask who wishes to know?" He asked Kate. At that moment, another, larger man approached the car, this time on Castle's side, flashing him a warm smile which Rick returned.

"I'm Detective Kate Beckett, NYPD, and this is Richar—"

Before she could finish her sentence, both of the men's eyes widened and they used all their force on both partners. They had hardly a second to realize what was happening before everything went back.

**A/N: Again, another short chapter. I apologize. Leave reviews anyways!**


	6. No Use

**A/N: Sorry this took forever! I got caught up in school and roleplaying.**

Rick groaned, clutching his throbbing head as he attempted to sit up. He was greeted with another blow to his head, this one self-inflicted. He blinked in surprise and reached into his pocket and removed his cell phone, quickly putting it onto the flashlight app and illuminating both of their faces.

They were clearly in a truck, Rick could now tell by the limited space they had. His head was throbbing harder by the second and he guessed he'd been hit by something and knocked out. He let his eyes get adjusted to the light as he turned to look at Kate, who was lying down next to him, eyes closed and hardly moving. In a moment of panic, Rick reached out and felt her neck, letting out a sigh of relief at the pulse he felt against her warm body. She was alive, they were alive, but they weren't safe.

At least, that's what Rick assumed. The last time this had happened he'd had a CIA contact to call for help. Now, he was completely alone, with no one but Kate. His phone, to his dismay, had no service so he couldn't even call for help. He had no idea whose car they were in and where they were, he just knew that they weren't moving.

Kate stirred, moaning lightly as she woke. Once she took in her surroundings, her eyes widened with panic for a moment before her arms found Rick. She calmed considerably at the sight of him.

"You alright?" Rick asked her. She nodded lightly, her hand flying up to clutch her head, which was throbbing as well.

"What's going on?" She asked Rick, trying to move but stuck in the limited space they both had.

"We're locked in a trunk," Rick replied, looking around for a way of escaping. Kate glared.

"Yeah, thanks," she said sarcastically. Rick glared back but his expression softened at the sight of her hand flying up to her head again. He hoped their injuries weren't too serious, but by the strength of the two men's blows, they might be.

"How are we gonna get out?" Kate muttered as she slammed a hand against the roof of the trunk.

Rick shrugged, fresh out of ideas. "I dunno," he admitted. Kate looked at him, and at that exact moment his phone died. Now left in complete darkness, Kate groaned at the added disadvantage. She felt hands pulling her close, and she didn't protest, glad to be able to lean into him and accept the light kiss to her forehead. Now that they had no light and no backup plan, they could only rely on each other.

"Why don't you do that thing?" Rick said quietly, his voice right next to Kate's ear. She ignored the shiver that went up her spine.

"Won't work in this car," she answered with a frown. Rick let out a sigh, wondering what they were going to do now. Kate settled on giving the car various kicks, but no one seemed to notice.

Outside, Esposito paced up and down the sidewalk.

"Dude, they'll be fine," his partner said. Esposito was unconvinced.

"Bro, they should be back by now. It's been hours. And their phones aren't working. Something's up, we should go after them."

Ryan let out a sigh and clapped his partner on the shoulder. "I'm telling you, they'll be fine." As if on cue, a loud slamming causing the detective to jump, looking around for the source of the noise. "What was that?"

They rounded a corner and were greeted with the sight of the exact car Castle and Beckett had just left in. Esposito looked at it questioningly.

"Wait, they're back already?" Ryan asked with a frown. Esposito shook his head with the same frown on his face. He looked inside, the paper with the address on it was gone and Rick's sandwich was messily thrown all over the passenger seat.

The slamming sounded again, and this time it was coming from the back of the car.

"They're in the trunk!" Esposito called to Ryan as he opened the trunk.

At the sight of the trunk opening, Kate shot up from Rick's arms. "Guys?" Her mouth dropped opened slightly at the sight of her fellow detectives and the scenery around them, they were back?

"What happened?" Esposito asked them as they hopped out of the trunk, too concerned with the fact that they were locked in their own trunk to point out that they were wrapped in each other's arms.

"I told them I was NYPD and they knocked us out and locked us in the trunk," she said, rubbing her face gently. "Can you guys pull up any cameras from around here? They must have dropped us off which means another car picked them up. Maybe we can get a license."

"On it," Ryan said, and the two ran off to do what they were told as Kate led Rick inside.

"They were hiding something," Rick said as four stood over a computer and began to watch the video from the cameras. "Why else would they knock us out and bring us back here?"

Kate hushed him as the video began, but she knew he was right. The video showed their car being parked and the same man that they had met at near the house leaving their car and hopping into a black van.

"No license plate," Ryan said dejectedly.

"They must have know there'd be cameras and took it off while they were in view, putting it back on later so they wouldn't get fined."

"How come no other criminals think like that?" Rick asked. Kate shot him a glare but wondered the same thing.

"Well now what?" She frowned.

"What do you mean now what?" Rick asked back with shock. "We go back!"

"Castle, they know we're cops, they'll just do it again. Or kill us for coming back."

"But I'm not a cop," he pointed out, excitement in his eyes.

"You were _with _a cop. They'll still consider you one."

"Why don't we send backup? They can't knock out a number of cops at once."

"No use, bro," Esposito interjected. "We lost the address, remember?"

"Just get it from the girl again! Look, we can't just –"

"Castle." Kate stopped him, looking at him with a sigh. "Just stop. Let's all just… sleep on it. We can decide what to do in the morning. It's getting late."

Despite himself, Rick nodded and slipped his coat back on.

* * *

"He asked you to _what?!_" Lanie almost yelled through the phone.

"Shut up," Kate snapped, ducking into the kitchen to as she held the phone tighter to her ear. Rick wasn't listening; he was in his study, completely absorbed by his writing. "Yeah, he did. While we were driving."

"… and?!"

Kate let out a sigh. "I don't know, Lanie. It's a bit soon…"

"Girl, you've been in love with that man for I don't know how long," Lanie interrupted. "So what if you only started dating a few months ago? You were taken by him long ago."

Kate wasn't sure how to answer that, so she kept silent for a moment. "Yeah, but…"

"No buts. You love him, right?"

At Lanie's words Kate looked back towards the door of the study and she bit her lip back. "More than anything," she said finally after a moment.

"Well then what the hell are you waiting for?" Lanie said, and Kate couldn't help but smile.

"I'll see you tomorrow, Lanie."

"Good-bye. And remember what I said!"

Kate rolled her eyes and hung up, Lanie's words running through her mind despite herself. Was she really ready to move in with Richard Castle? Despite her mind telling her no, her heart told her that even if he asked her to marry him she'd say yes in a heartbeat.


	7. Third Witness

This was the part she hated the most, the part where had to go back into hiding. They'd come for Amber, they were sure to come after her now. It was only a matter of time; people like her didn't last long in the real world. That was a fact she'd learned from a young age, something she'd had drilled into her head from the moment she was born. You escape, you die.

She knew it. Amber knew it. So why had she spent her days, acting like a real person, going to school and making friends? That just wasn't something you did. You put yourself in danger and you put everyone you were close to in danger. The people who ran the institute were ruthless; they'll kill anyone who gets in your way. Amber had been reckless, and that she'd almost got her little ginger friend killed.

Luckily, she was there at the time. She'd been following Amber, not to protect her or defend her if need be, but as bait. They were going to come after Amber, that much was clear. She'd planned on following them and taking the man a hostage, leverage to get her own safety from the institute. But it hadn't exactly worked as planned; she had to let him go in order to save an innocent girl's life.

Which she wouldn't have had to do in the first place had it not been for Amber's stupidity.

But, she didn't regret it. She saved someone, which was what mattered. Maybe more people had escaped and she could use them, but let's face it, she would have found them by now. Amber and she had been planning to escape their entire lives, and they were the only two daring enough to do it. After many beatings and discouragement, they'd finally done it, and they were free to the world – but only if they were careful.

Oh, she'd been more than careful. She changed her name every year, never stayed in the same place for more than two nights in a row, and hardly walked the streets at night if she could help it. She hadn't gone to school, or got a job, or made friends. The only thing she had was the clothes on her back. She hadn't had a decent meal in her entire life.

All they fed her in the institute was scraps, hardly enough to survive. She and Amber were some of the lucky ones, the ones who survived; the success stories. Once she'd escaped, she never considering going to the police about this. Sure, it was illegal to experiment on humans, especially children and embryos, but they'd put her in a freak show or a mental hospital. She'd rather be free and dirt poor.

Days after she saved Alexis, she'd come to terms that maybe going to the police would be a good thing. Maybe they'd be able to finally put a stop to this experimenting, and maybe she'd save some lives. The only thing she'd want is what she already has: freedom. As long as they don't take that away from her, she'd help them take the institute down.

All this was running through the young girl's head as she stood outside the Prescient. Her hands were tucked into her leather jacket, one she'd taken from a guard she'd beat down during her escape. A gun she hardly used was sitting under the waist of her jeans, covered by her t-shirt. They'd escaped only a few years ago, and the shirt was big on her then, so it still fit her. Despite her rugged appearance, her hair was nicely combed and her face had a bit of make up on it. Ah, the advantages of knowing how to break into places.

With the tiniest of smirks, she entered the building, making her way to Homicide and entering the floor with stride. A few looks passed though the detectives as she walked to the captain's office, not afraid of anyone's wrath, knowing she could take them all down if she needed to.

Captain Gates looked up in surprise at the new visitor in her office.

"And who are you?" She asked.

"Gracie, I'm here to give you information about Amber Middleton's murder. However I have one request."

The Captain raised her eyebrows. "What kind of request?" She asked dangerously.

"I want complete freedom. I don't want to be locked up or put in a hospital – I want to walk out of here with my freedom."

The Captain clenched her jaw but nodded towards the door. Taking that as an invite, the girl left the room and approached the detectives, who were watching the short exchange curiously. The pretty girl detective's eyes widened at the sight of her, and Gracie could tell that she knew who she was. She gestured towards the couch, and the detectives followed.

"You're our second witness," the writer-boy, Richard Castle, pointed out as she sat down.

"I wouldn't put it that way, but sure," Gracie replied, putting on a small smile for the detectives.

"What happened, that night?" The girl detective asked. Gracie leaned forward in her chair.

"Miss Detective, with all due respect, if you want the real story, you need to shut up and let me tell you from the beginning."

The Detective blinked back her surprise, but said nothing further, allowing Gracie to begin her story.

"I grew up in the institute. I was one of the few experiments that actually worked. I was a success story… and so was my best friend Amber. We were child experiments. The purpose of their experimenting on innocent children was the simple reason of pleasure. See, they do it to entertain. Granted, they probably sell a few; use a few for medical breakthroughs, but when they get bored they just make a new one."

"Where do they get the kids from?" The cute Detective, Detective Ryan asked.

"Snatch some. Birth some. But some are homeless children, like me and Amber. At 15, Amber and I formulated a plan to escape. The thing about these guys is that if you try to escape, you're done. It's nearly impossible to escape; you're dead before you reach the doors. They didn't want word of it getting it, in case cops like you find out about it and shut them down and arrest them for life."

"What will they do if they find out you've come to us?" Richard Castle asked.

"Hunt me down. Kill me. Take my body away and burn it, most likely. No evidence left behind of the experimental institute."

The Detectives exchanged glances. "No worries, they'd chased me down before but I outsmart them every time. Anyways, Amber and I escaped. We were the first to do so – we were strong and we got out. We went our separate ways, I became a homeless drifter – which is the safest route, and Amber attempted to make a name for herself."

Gracie stopped talking for a moment to take a sip of the water they'd gotten for her. "That was a big mistake. People like us; we're too dangerous in the real world, especially with the institute on our ass. It was only a matter of time before they hunted her down and killed her. I saw it coming, she wasn't being safe. She was putting her friends in danger and her name out there. Even though she'd made up the name herself and we'd faked her entire background, they were bound to find her eventually.

"Me, I took the smart route. I became homeless, I became a nameless hobo, I lived off scraps and shit I could steal. Granted, it's not the best way to leave, but I figure I was free and I had my pride so I managed pretty well. Anyways, I'd been worried for her lately. Worried for that red-headed girl she'd become close with. So, I began following her. Safely, of course. When I noticed an odd man had an eye on her, I stole a phone from a local store and managed to scavenge enough cash for a short plan. Don't ask me how," she added, twinkle in her eye with sly grin on her face.

"I started giving her these phone calls, telling the fool to stop going outside, keep safe, drop out, that she was being followed. I figure now that they didn't help much, just made her more paranoid. I guess I sorta figured that at the time too, 'cause I began following her everywhere she went just in case. When I realized she was in too deep and marked for death, I decided to use her to my advantage. She became my bait."

She raised her hands at the shocked expressions on the Detectives' faces. "I know, I know, it's horrible, but I figured it needed to be done. I would wait until they attacked, then stop the attack halfway through and take the attacker as a hostage. The only way I'd free the guy would be if the institute granted me complete freedom from them. I'd swear to keep their secret, they'd give me freedom, they get their guy back, and all would be right with the world. I'd take Amber with me and we'd run off together, never to be seen again.

"Obviously, that didn't work out as planned." Gracie raised her head to look at Richard Castle as she took another sip of her water. It was good; she hadn't had water like this in her whole life. Was it sparkling? "As soon as I saw Amber out with that redhead and the man following them into the place, I knew my plan was dead in the water. Once they ran out, I followed. I didn't get there on time, once I entered the alley Amber was dead and the man had his knife perfectly placed to slit the innocent girl's throat. I pulled her out of the war faster than the speed of his blade, throwing her into the trash cans behind me and shoving the attacker back. I stabbed him right in the shoulder and he ran faster than a damn puppy." Gracie chuckled in spite of herself. "Then I turned to that little redhead girl, told her she was gonna be alright. I called up the cops, let 'em know where the body was, smashed the phone, and took off. I wasn't expecting to come here but I figured if I could get the cops to help take down the institute I can save lives while keeping mine granted for safety." She leaned back in her seat, looking at the faces of everyone else in the room. "And that's the whole story."

* * *

"She's Alexis's age."

Kate turned to see Rick standing behind her, a weird expression on his face. They were looking at the murder board, it was fuller than ever. Gracie was asleep in the break room; they'd practically had to force her to stay, even just for a while to catch up on her sleep in a place that wasn't a dark alley or the top of a building. Kate nodded lightly at her partner.

"I mean, she's so young. Poor kid."

"She's managed," Kate said, turning back to look at the murder board. "She's strong."

"Alexis wants to come down and see her," he added. Kate looked at him in surprise.

"Well, she did save her life. No need to sound so disapproving."

Rick shrugged. "I just don't like her much is all."

"Castle, if it wasn't for that Gracie Alexis would've ended up like Amber."

Rick took a moment to realize that, and the shame showed on his face. "But still. It's a bit dangerous for Alexis to even be around her, with the hunting…"

Kate turned to Rick. "She wants to see her, not go out with her."

There was a moment of silence before he spoke again. "Should I go get Alexis, then?"

"She isn't going to stay much longer," Kate pointed out with a small nod towards the sleeping figure on the couch.

"True," Rick said, giving Kate a light kiss on the cheek despite himself and heading out the door.

* * *

Gracie always had the same nightmares – and in every one of them she ended up dead. That was her worst fear – ending up dead. She'd worked her entire life, fought through the hardest things to survive, and it scared her that someday that would all end. Whether it was from natural causes or a knife through her heart – it was going to happen someday. The latter scared Gracie the most, as much as she acted brave around them the truth was that she was scared; very scared, of the men that were dedicated their lives to hunting her down.

After a short spout of sleep, her body finally decided it was enough. She hardly got sleep anymore, she was simply too used to running on little hours of sleep. She blinked herself into true awakeness, sitting up on the surprisingly comfy couch that she'd had the pleasure to nap on today. She pushed her hair back from her face and groaned lightly, stretching a bit and yawning herself awake.

"Hi," came a familiar voice from the door. She blinked as she turned her head and met eyes with the redhead girl from the alleyway.

"Hi," Gracie said back, trying not to let the surprise show on her face. She honestly thought she'd never see this girl again, what did she want, to thank her? Gracie had done enough bad in her life to know that she wasn't a good person, even if she did save someone's life.

She kept her gaze on the redhead as she sat down next to her. "I… want to thank you. For saving my life."

Gracie shook her head at the girl's comments. "Don't thank me."

"No, seriously." She turned so she was facing Gracie. "I owe you my life. How can I make it up to you?"

Gracie almost laughed. There was nothing this girl could do to improve her life, and she definitely didn't need to repay her. But she stopped herself, thinking of one thing that she suddenly found herself wanting. "I don't know what ice cream tastes like…" she stared.

Alexis's eyes widened. "You've got to be kidding me. Alright, ice cream it is then." She stood, taking Gracie by the hand and forcing her to stand with her. Gracie blinked in surprise, but smiled despite herself. "Come on…"

"Gracie," she said with a smile.

"Alexis."

The two girls smiled at each other and Alexis led the way out of the break room, Gracie in tow. Despite herself Gracie found herself liking Alexis, though she still didn't like the look her father gave them as they left.


End file.
